As comets move close to the Sun, they develop tails of dust and ionized gas. Comets have two main tails, a dust tail and a plasma tail. The dust tail appears whitish-yellow because it is made up of tiny particles â about the size of particles of smoke â that reflect sunlight. Dust tails are typically between 1 and 10 million kilometers (about 600,000 to 6 million miles) long.
Hyperhidrosis, or excessive sweating, is a common disorder which produces a lot of unhappiness. An estimated 2-3% of Americans suffer from excessive sweating of the underarms (axillary hyperhidrosis) or of the palms and soles of the feet (palmoplantar hyperhidrosis). Underarm problems tend to start in late adolescence, while palm and sole sweating often begins earlier, around the age 13 (on the average). Untreated, these problems may continue throughout life. Sweating is embarrassing, it stains clothes, ruins romance, and complicates business and social interactions.
The most common diseases to cause excessive sweating are diabetes and hyperthyroidism. Diabetes mellitus is a disease of poor glucose (sugar) control. Over time, diabetes disrupts the proper function of the ANS. Diabetes is also associated with obesity, which itself can cause excessive sweating. An easy way to find out if you have diabetes is to have your blood glucose (sugar) checked by your primary doctor with a simple blood test.